1. Field of the Invention
The present invention relates to a semiconductor device and manufacturing method thereof and, more specifically, to a vertical semiconductor device having superior characteristics and to a method of manufacturing the same. Description of the
2. Background Art
Vertical semiconductor devices, including both light emitting devices and electronic devices, have characteristics that packaging is easy and area efficiency is high. As a method of manufacturing a vertical semiconductor device having such characteristics, a method of joining semiconductor layers grown on an underlying substrate to a supporting substrate different from the underlying substrate has been proposed.
By way of example, Japanese Patent Laying-Open No. 2010-212719 (PTL 1) discloses forming rugged patterns on a surface of a semiconductor layer (a surface of an n type semiconductor layer) after removing an underlying substrate from semiconductor layers grown on the underlying layer, to enhance light extraction efficiency.
Japanese Patent Laying-Open No. 2007-158334 (PTL 2) discloses growing semiconductor layers with an etching stop layer interposed, on an underlying substrate, so as to stop etching of a semiconductor layer after removing the underlying substrate at the etching stop layer, and thereby to reduce damage on the semiconductor layer (n type semiconductor layer) and to improve contact characteristic of an n side electrode.
Further, Japanese Patent Laying-Open No. 2010-232625 (PTL 3) discloses joining a group III nitride semiconductor layer on a supporting substrate with a buffer layer interposed, and removing the buffer layer by etching, to ease laser lift-off of the supporting substrate.